"""Utility & helper functions."""

from typing import Union

from langchain.chat_models import init_chat_model
from langchain_core.language_models import BaseChatModel
from langchain_core.messages import BaseMessage
from langchain_qwq import ChatQwen, ChatQwQ

from .models import create_qwen_model


def get_message_text(msg: BaseMessage) -> str:
    """Get the text content of a message."""
    content = msg.content
    if isinstance(content, str):
        return content
    elif isinstance(content, dict):
        return content.get("text", "")
    else:
        txts = [c if isinstance(c, str) else (c.get("text") or "") for c in content]
        return "".join(txts).strip()


def load_chat_model(
    fully_specified_name: str,
) -> Union[BaseChatModel, ChatQwQ, ChatQwen]:
    """Load a chat model from a fully specified name.

    Args:
        fully_specified_name (str): String in the format 'provider:model'.
    """
    provider, model = fully_specified_name.split(":", maxsplit=1)

    # Handle Qwen models specially with dashscope integration
    if provider.lower() == "qwen":
        return create_qwen_model(model)

    # Use standard langchain initialization for other providers
    return init_chat_model(model, model_provider=provider)
